Returning from her informal EU summit in Malta last week, the Prime Minister told MPs “our European partners now want to get on with the negotiations” and the Commons should not “obstruct the democratically expressed wishes of the British people”.

However, Alexander Stubb, a Finnish politician, advised Mrs May to not rush into negotiations because some members of the European Parliament are still frustrated by Brexit and want to punish the UK.

Speaking on BBCNewsnight, Mr Stubb said: “[Brexit] is definitely a big crack and many of us are still are umming and ahhing – but I think we are all very pragmatic about it.

“I for one will be trying to make the best out of a very difficult situation.”

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The former Finnish PM warned Theresa May that some Europeans still want to "punish" her over Brexit

There are people on the Continent who want to punish Britain for Brexit

Alexander Stubb

The politician had previously predicted wide-scale economic damage from the UK’s European divorce, suggesting Mrs May’s desire for a “clean exit” was likely to end with a “messy” Brexit.

Mr Stubb continued: “In the long-term economic cycle I think we will have to see what the effects are.

“There are people on the Continent who want to punish Britain for this – I don’t want to do that, I actually want to find a good deal for Britain and for Europe as well.

“We have to live with this new reality, but we have to understand that it weakens everyone.”

Mrs May and the Conservatives have published a white paper outlining their negotiation strategy for when Article 50 is triggered.

The document features her 12 “principles”, which the Prime Minister will take to the EU as part of her goals for Brexit.

Opting to favour immigration controls over single market access, she has promised voters a new system to control EU migration but warned it may have to be phased in to give businesses time to prepare for the changes.

Mr Stubbs, who is also a former MEP, claimed “you never get everything you want” in negotiations, insisting Theresa May will have to come to a compromise with her European colleagues.

“I think usually a list is a starting position of the negotiations,” he added.

Theresa May's Brexit plan Mon, January 16, 2017

It's finally here!

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Continued cooperation with the EU to tackle terrorism and international crime.

“It’s impossible to say at this stage [what Britain will miss out on]. The Brexit negotiations, themselves, are going to take about two years and they, of course, at the end of the day what we decide one of two things: the exit date and the second one is probably linked to money.

“It would be wonderful if she did [get her favoured deal] but I think we need to work in that direction.

“No-one wants to isolate the UK in terms of trade, there is no question about that. In terms of taking control of your own laws, yes that will happen but first, you’ll have to take lock, stock and barrel at 200,000 pages of our key [laws] and start moulding those around.”

Mr Stubb concluded that a “no nonsense” approach from civil servants and UK ministers has left him “optimistic” Brexit will end in success.